Today is the day for the next note change in this performance of John Cage's As Slow As Possible.
What? You don't want to wait so long for the piece to continue? It can be performed more quickly than this. You can buy a CD of the 71-minute version at Amazon.com. Watch a performance of that short one here:
I'll be long dead by the time the 639 year long performance is completed in 2640.